Kouta Hasegawa is a completely normal high school student who likes his Pompompurin stuffed animal, a Sanrio character modelled after a Golden Retriever, which his grandmother gave him when he was young. However, an incident in which other kids accused him of being girly for liking Sanrio characters made him ashamed of his attachment to Pompompurin. Through a series of unexpected events, Kouta ends up meeting others...